Dietary Supplementation with L-Serine Regulates Growth Performance, Carcass Traits, Meat Quality, and Intestinal Development in Broilers

This study evaluated the effects of additional L-serine supplementation in diets on performance, carcass characteristics, meat quality and small intestine development in broilers. A total of 300 one-day-old unsexed Yellow-Feathered broilers were randomly divided into three groups with 10 replicates of 10 birds each. The broilers were fed basal diet (CON), basal diet + 0.085% L-Alanine (Isonitrogenous) and basal diet + 0.1% L-serine (0.1% Ser), respectively. The whole trial lasted for 42 d. The results showed that 0.1% L-serine supplementation in broiler diets could increase final body weight and average daily weight gain (p < 0.05) and had no significant effect on serum biochemical indexes (p > 0.05). Compared with the Isonitrogenous group, the 0.1% Ser group significantly reduced FCR (p < 0.05). Regarding meat quality, the 0.1% Ser group significantly increased by a*45 min and 24 h pH values, while it decreased by b*45 min values in both breast and leg muscles (p < 0.05) and reduced cooking loss in leg muscles (p < 0.05). L-serine effectively reduced localized fat deposition and promoted intestinal development. Morphometric analysis revealed significantly increased small intestinal villus length and villus length/crypt depth ratio in the 0.1% Ser group (p < 0.05). In conclusion, L-serine can be used as an effective supplement in broiler farming to improve its productivity.